White noise machines or sleeping machines used to help infants sleep can exceed noise levels for hospital nurseries and potentially damage the hearing of the sleeping infants, a Canadian study shows. For adults, the sounds produced by white noise machines aren’t dangerous, but the ears of infants are more delicate and more susceptible to sounds.
Sounds of white noise machines
A Canadian research team tested 14 different white noise machines with a total of 65 sounds. The sounds were played at a maximum volume level at three distances to simulate different scenarios. The first was from 30cm, to simulate the device placed on a crib rail, the second distance was at one metre, simulating placement near a crib and finally from two metres, simulating placement across the room.
When placed at 30cm and one metre, all the devices exceeded 50dB, the recommended decibel limit for hospital nurseries. Three of the machines were even capable of producing sound levels of 85db when placed on the crib rail.
At two metres, the researchers found that all but one of the devices surpassed the hospital limit.
Parents should be aware
Babies’ ears are different from adults’. They are more sensitive, because the small ear canals amplify sounds.
Based on their results, the Canadian researchers suggest that parents place the sleeping machines as far away from their infants as possible and set the volume as low as possible.
They also recommend parents limit the length of time the machine is playing by possibly using an automatic turn-off function or turning the device off when the baby has fallen asleep.
About the study
The study was conducted by a research team from the Hospital for Sick Children in Toronto, Canada and was published in The Journal of Paediatrics.